Question

What was the temperature anomaly in Buffalo, NY on August 27 , 2019? Give your answer in °C. Answers within ±3°C of the correct answer are marked correct.

The long-term average temperature for August in Buffalo is 20 °C. Using this information and your answer from Q8, what was the temperature in Buffalo on August 27, 2019? Give your answer in °C.

Hotter objects emit _________ than cooler objects

a. more energy at redder wavelengths

b. more energy at bluer wavelengths

c. less energy at redder wavelengths

d. less energy at bluer wavelengths

Match the Sun and Earth with the wavelength of light that it primarily emits.

Earth

Sun

A. Longer wavelength

B. Shorter wavelength

Use the graphing tool at https://phet.colorado.edu/sims/blackbody-spectrum/blackbody-spectrum_en.html to investigate the wavelengths of light that would be emitted by stars of certain temperatures. Using this tool, you can adjust the temperature using either by typing the temperature into the white box on the right, or by adjusting the slider underneath the white box.

For each star, match it to its peak wavelength.

T = 5500 K (the sun)

T = 4000 K

T = 3,000 K

T = 6000 K

T = 4700 K

A. Green

B. Red

C. Infrared

D. Yellow

E. Blue

The average temperature at the earth's surface is 14°C. What is this temperature in Kelvin?

Use your answer from Q17 and the Stefan-Boltzmann equation to calculate how much power each square meter of the earth's surface radiates. Give your answer in W/m2. Round to the nearest W/m2.

In what part of the electromagnetic spectrum does the earth radiate light? Answer in a single word (no numbers).

Consider your answers to the previous three questions. If the surface of the Earth is radiating that much energy, why do we not see the ground glowing? Answer in 1-2 sentences.

Temperature Anomaly (°C) on August 27, 2019 30 20 10 -10 -20 -30

Answer 1

2. b. more energy at bluer wavelengths

Because hotter objects emit more energy in blue wavelength and cooler objects emit more energy in red wavelength.

3. Earth: A. Longer wavelength

     Sun: B. Shorter wavelength

Because Sun is very hot and emits shorter wavelengths and once the earth absorbs solar energy, the ground re emits it as longer wave length.

4.

T = 5500 K (the sun) : D. Yellow

T = 4000 K : A. Green

T = 3,000 K : B. Red

T = 6000 K : E. Blue

T = 4700 K : C. Infrared

Because the hottest stars emit blue light and coolest stars emit red light.

5. The average temperature at the earth's surface is 14°C.

The kelvin temperature is 14+273 = 287 K

According to Stefan-Boltzmann equation

Energy Flux E = $\sigma$T⁴

$\sigma$ =5.6703*10^-8 W/m²K⁴

Energy Flux E = $\sigma$T⁴

Energy Flux E = 5.6703*10^-8 W/m²K⁴ * (287 K)⁴

Energy Flux E = 384.710 W/m²

6. Infrared

Because Incoming solar radiation reaches the earth as visible light After being absorbed by the earth's surface heating it and this energy is radiated as infrared wavelength of electromagnetic spectrum of radiation.

7. f the surface of the Earth is radiating that much energy, the ground not glowing because of the energy balance between incoming radiation and outgoing radiation. How much energy received by the earth is equal to the the outgoing energy radiation from earth.